特大型机组励磁系统关键技术研究与应用

Research and application on key technology in excitation system of giant generator

特大型机组励磁电流大、电压高,在励磁变压器和灭磁系统的选型、灭磁过程计算以及整流柜冷却设计等方面给励磁系统设计带来巨大挑战。为解决这些问题,开展了国内外调研,并进行了相关基础研究。联合中国制造单位研制出3000 kVA大容量单相励磁变压器样机,首次提出了交直流冗余灭磁方案;研究出灭磁过程的工程计算方法,以及封闭环境下整流柜冷却系统。研究结果表明,基于以上关键技术所提出的励磁系统设计方案,满足特大型发电机安全可靠运行要求。该方案成功应用于三峡电站和国内其他特大型发电机组,并取得了一系列创新成果。

The large excitation current and high excitation voltage of giant generator have brought great challenges to the design of excitation systems inthe selection of excitation transformers and de-excitation systems,calculation of the de-excitation process,and the design of cooling of rectifier cabinets.In order to solve these practical engineering problems,domestic and foreign researches had been conducted and relevant basic research had been carried out.In collaboration with domestic manufacturing factory,a prototype of 3000 kVA large capacity single-phase excitation transformer had been developed.For the first time,an AC and DC redundant de-excitation scheme had been proposed.And engineering calculation methods for the de-excitation process as well as a cooling system for the rectifier cabinet in a closed environment had been studied.The results showed that the design scheme of excitation system,which was put forward to meet the requirements of safe and reliable giant generator operation based on the above key technologies,had been successfully applied in the three Gorges Power Station for the first time and other giant power units in China,and a series of innovative results came out.